Concierge.com's insider take:

Housed in a modern building at the mouth of the Charles River with views of the Boston skyline, the Museum of Science is one of the best of its kind. Kids love the hands-on exhibits that demonstrate everything from biology to computers to physics. They can determine how much sugar is in a bottle of Coca-Cola, measure the volume of their lungs, and investigate the mysteries of lightning with the world's largest Van de Graaff generator. There's also an adorable troupe of live cotton-top tamarin monkeys who live here to help the museum staff study evolution, a planetarium, and an Omnimax theater that shows science- and technology-oriented films, such as Galapagos. Volunteers roam the building on Segways to dole out information. The Butterfly Garden, a humid greenhouse opened in 2005, flutters with about 100 butterflies (monarchs, owl butterflies, and bamboo pages) and exotic plants, like the Stachytarpheta (or Blue Rat's Tail). The place is generally mobbed by school groups on weekdays, and herds of suburban families on weekends (a huge parking deck sits next to the building to accommodate them). Visit on a Friday evening after 5 p.m. to avoid the crowds.

Open daily 9 am to 7 pm (until 9 pm on Fridays) between July 5 and Labor Day; 9 am to 5 pm (until 9 pm on Fridays) during the rest of the year.